The A15 chip is not required for FaceID. The iPad Pro has both M1 chip and FaceID, so its not a processor issue.
Also FaceID on a Mac is FAR LESS important if you have setup your Apple Watch to unlock -- works fantastic even on older macs (like my 2015 iMac at work).
Also FaceID on a Mac is FAR LESS important if you have setup your Apple Watch to unlock -- works fantastic even on older macs (like my 2015 iMac at work).